WASHINGTON (Reuters) - U.S. interests sometimes
clash with its support for democracy in the Middle East,
Secretary of State Hillary Clinton acknowledged Monday, but
she said democratic freedoms were the best guarantee of
stability in the long run.

In a speech on Washington's response to the Arab Spring
that toppled several U.S. allies, Clinton implicitly faulted
the military council that succeeded former Egyptian President
Hosni Mubarak for moving too slowly on elections.

She also acknowledged that the United States sometimes
deals differently with pro-democracy movements, saying no two
situations are the same and that diverging U.S. interests
sometimes force it to adopt varying stances.

Clinton used her her speech to the National Democratic
Institute to address questions such as why the United States
built a military coalition to force Libyan dictator Muammar
Gaddafi from power while it has been more cautious in Syria.

The U.S. justification for intervention in Libya -- to
protect civilians -- would also appear valid in Syria, where
activists say that Syrian President Bashar al-Assad's forces
have killed hundreds of civilians seeking an end to his rule.

"Sometimes, as in Libya, we can bring dozens of countries
together to protect civilians and help people liberate their
country without a single American life lost," she said.

"In other cases, to achieve that same goal, we would have
to act alone, at a much greater cost, with far greater risks
and perhaps even with troops on the ground," she added.

"Our choices also reflect other interests in the region
with a real impact on Americans' lives -- including our fight
against al Qaeda; defense of our allies; and a secure supply of
energy," she said.

"Over time, a more democratic Middle East can provide a
more sustainable basis for addressing all three. But there will
be times when not all of our interests align. We work to align
them, but that is just reality," she added.

ROOMFUL OF UNELECTED OFFICIALS

In the careful language of diplomacy, Clinton had tough
words for the military council that took power in Egypt after
forcing long-time U.S. ally Mubarak from office following mass
protests against his three-decade authoritarian rule.

"If, over time, the most powerful political force in Egypt
remains a roomful of unelected officials, they will have
planted the seeds for future unrest. Egyptians will have missed
a historic opportunity. And so will we."

Clinton said the United States must be prepared to work
with democratically elected leaders that do not agree with it,
including Islamist parties such as that which just won
Tunisia's first free election last month.

"What parties call themselves is less important than what
they do," Clinton said, saying parties which respect the rule
of law, renounce violence, protect freedoms of speech and
assembly and the rights of women should all be regarded as
legitimate political players.

Clinton said the United States would continue to have
"frank conversations" with long-time allies such as Bahrain,
where the Sunni ruling family brought in troops from Sunni
allies Saudi Arabia and the United Arab Emirates to help crush
a protest movement earlier this year.

"Mass arrests and brute force are at odds with the
universal rights of Bahrain's citizens and will not make
legitimate calls for reform go away," Clinton said, saying the
tiny Gulf country's monarchy had made public promises to begin
political dialogue and investigate abuses.

"We intend to hold the Bahraini government to these
commitments and to encourage the opposition to respond
constructively to secure lasting reform," she said.

In other cases such as Syria, where the Assad government
continues to respond violently to political protests, the
message must be equally clear, she said.

"Those leaders trying to hold back the future at the point
of a gun should know their days are numbered," she said, adding
that another long-time U.S. foe, Iran, showed "breathtaking
hypocrisy" when it claimed to back democracy abroad while
killing protesters at home.

Clinton acknowledged that the issue of the Palestinians,
who have sought U.N. recognition of their statehood despite
Israeli protests and a U.S. vow to veto the measure in the U.N.
Security Council, rankled many across the Middle East.

But she stressed the U.S. position that only negotiations
with Israel can produce a real, viable Palestinian state living
side by side in peace with Israel.

"It would shortsighted to think either side can simply put
peacemaking on hold until the current upheaval is done. The
truth is, the stalemate in the Arab-Israeli conflict is one
more status quo in the Middle East that cannot be sustained,"
she said.
(Writing by Arshad Mohammed and Andrew Quinn; editing by
Anthony Boadle)